Collateralized Transactions - Collateral Pledged (Details) - USD ($) $ in Thousands	Feb. 28, 2018	Nov. 30, 2017
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	$ 2,372,473	$ 2,843,911
Repurchase Agreements	16,755,127	19,829,249
Obligation To Return Securities Received As Collateral		103
Total	19,127,600	22,673,263
Cash
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0
Repurchase Agreements	213,035
Total	213,035
Corporate equity securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	1,934,024	2,353,798
Repurchase Agreements	309,860	214,413
Obligation To Return Securities Received As Collateral		0
Total	2,243,884	2,568,211
Corporate debt securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	363,344	470,908
Repurchase Agreements	2,027,899	2,336,702
Obligation To Return Securities Received As Collateral		0
Total	2,391,243	2,807,610
Mortgage- and asset-backed securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	2,961,222	2,562,268
Obligation To Return Securities Received As Collateral		0
Total	2,961,222	2,562,268
U.S. government and federal agency securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	75,105	19,205
Repurchase Agreements	8,269,477	11,792,534
Obligation To Return Securities Received As Collateral		0
Total	8,344,582	11,811,739
Municipal securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	547,817	444,861
Obligation To Return Securities Received As Collateral		0
Total	547,817	444,861
Sovereign obligations
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	2,124,652	2,023,530
Obligation To Return Securities Received As Collateral		103
Total	2,124,652	2,023,633
Loans and other receivables
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	301,165	454,941
Obligation To Return Securities Received As Collateral		0
Total	$ 301,165	$ 454,941

Amount, after effects of master netting arrangements, of derivative liabilities, securities sold under agreements to repurchase and securities loaned offset against a right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226016-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL34722452-111729

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=64858031&loc=SL34722452-111729

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